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A Deep Neural Network Based on Two-Stage Training for Estimating Heart Rate Variability From Camera Videos
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作者 Lan Lan Jin Yin +6 位作者 Haohan Zhang Hua Jiang Rui Qin Xia Zhao Yu Zhang Yilong Wang Jiajun Qiu 《Health Care Science》 2026年第1期74-84,共11页
Background:Studies have shown that heart rate variability(HRV)is a predictor of the prognosis of cardiovascular diseases.Contact heartbeat monitoring equipment is widely used,especially in hospitals,and benefits from ... Background:Studies have shown that heart rate variability(HRV)is a predictor of the prognosis of cardiovascular diseases.Contact heartbeat monitoring equipment is widely used,especially in hospitals,and benefits from the rapidity and accuracy of the detection of physiological health indicators.However,long-term contact with equipment has many adverse effects.The purpose of this study was to improve the accuracy of HRV detection via noncontact equipment,thus enabling HRV to be assessed in various scenarios.Methods:A novel deep learning approach was proposed for measuring heartbeats through camera videos.First,we performed facial segmentation and divided the face into 16 grid cells with different light balance scores.After the trend is filtered by the Hamming window,a transformer-based neural network is used to further filter the signal.Finally,heart rate(HR)and HRV are estimated.Results:We used 1 million synthetic data points for pretraining and a public dataset in combination with a dataset that we constructed for task training.The final results were obtained on a test dataset that we constructed.The accuracy for HR with a low light balance score(0.867-0.983)was greater than that with a high score(0.667-0.750).Our method had higher accuracy in estimating HR than traditional filtering methods(0.167-0.417)and state-of-the-art neural network filtering methods(0.783-0.917)did.The root mean square error of the HRV from the time domain was the lowest,and the correlation index score was the highest for the HRV from the frequency domain estimated by our method compared with those estimated by two neural networks.Conclusions:Light balance,large sample training,and two-stage training can improve the accuracy of HRV estimation. 展开更多
关键词 CAMERA cardiovascular disease deep learning heart rate variability pretraining
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Enhanced moisture-sensitivity increased the growth variability of Picea purpurea in the northeastern Tibetan Plateau
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作者 Wenxin Yu Bo Wang +2 位作者 Tuo Chen Guobao Xu Guoju Wu 《Journal of Forestry Research》 2026年第2期213-223,共11页
Tree growth variability is a key determinant of forest stabilities.Previous studies have shown that recent climate change has increased variability in tree growth,while others have challenged this viewpoint,leading to... Tree growth variability is a key determinant of forest stabilities.Previous studies have shown that recent climate change has increased variability in tree growth,while others have challenged this viewpoint,leading to ongoing debate in this field.Moreover,gaps remain in understanding the climatic mechanisms driving increased tree growth variability,particularly for species simultaneously limited by multiple climate factors.In this study,we assessed the temporal trends in variability of Picea purpurea radial growth and its linkage with growth-climate sensitivity utilizing dendrochronological methods.Our results revealed a significant increase in P.purpurea radial growth variability from 1960 to 2020,as indicated by continuous rises in the standard deviation,coefficient of variation,and mean sensitivity of tree-ring width indices.The increased frequency of extreme growth declines further supported this finding.Furthermore,moisture condition in July was identified as a key limiting factor of P.purpurea growth.Notably,the strengthening relationship between tree-ring width indices and vapor pressure deficit(VPD)suggests that the moisture sensitivity for P.purpurea growth has increased over the period 1960-2020.This enhanced sensitivity to VPD,whose interannual variability has also increased synchronously,may have contributed to the rise in P.purpurea growth variability.Additionally,the maximum temperature in May was positively correlated with P.purpurea growth;however,there is little evidence that this factor contributed to the observed increase in growth variability.These findings provide new insights into P.purpurea growth trends and improve our understanding of the potential future impacts of climate change on forest ecosystems. 展开更多
关键词 Tree growth variability Growth-climate response TREE-RING Picea purpurea
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Research Progress on Spatiotemporal Variability of Rice Planting Based on Satellite Remote Sensing Monitoring
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作者 Qi ang HU Aichuan LI +2 位作者 Xinbing WANG Francesco Marinello Zhan SHI 《Agricultural Biotechnology》 2026年第1期76-81,共6页
As a vital food crop,rice is an important part of global food crops.Studying the spatiotemporal changes in rice cultivation facilitates early prediction of production risks and provides support for agricultural policy... As a vital food crop,rice is an important part of global food crops.Studying the spatiotemporal changes in rice cultivation facilitates early prediction of production risks and provides support for agricultural policy decisions related to rice.With the increasing application of satellite remote sensing technology in crop monitoring,remote sensing for rice cultivation has emerged as a novel approach,offering new perspectives for monitoring rice planting.This paper briefly outlined the current research and development status of satellite remote sensing for monitoring rice cultivation both at home and abroad.Foreign scholars have made innovations in data sources and methodologies for satellite remote sensing monitoring,and utilized multi-source satellite information and machine learning algorithms to enhance the accuracy of rice planting monitoring.Scholars in China have achieved significant results in the study of satellite remote sensing for monitoring rice cultivation.Their research and application in monitoring rice planting areas provide valuable references for agricultural production management.However,satellite remote sensing monitoring of rice still faces challenges such as low spatiotemporal resolution and difficulties related to cloud cover and data fusion,which require further in-depth investigation.Additionally,there are shortcomings in the accuracy of remote sensing monitoring for fragmented farmland plots and smallholder farming.To address these issues,future efforts should focus on developing multi-source heterogeneous data fusion analysis technologies and researching monitoring systems.These advancements are expected to enable high-precision large-scale acquisition of rice planting information,laying a foundation for future smart agriculture. 展开更多
关键词 Satellite remote sensing Rice cultivation Spatiotemporal variability MONITORING Research review
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Temporal Variability Analysis of Cortical Blood Flow in Rats with Hyperacute Cerebral Ischemia
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作者 Bochao Niu Benjamin Klugah-Brown +2 位作者 Yang Xia Dezhong Yao Bharat B.Biswal 《Neuroscience Bulletin》 2026年第1期55-74,共20页
Cerebral ischemia restricts cerebral blood flow(CBF),leading to unstable hemodynamics.Past studies of ischemia mainly focused on cortical CBF reduction.However,its impact on hemodynamic changes,especially temporal var... Cerebral ischemia restricts cerebral blood flow(CBF),leading to unstable hemodynamics.Past studies of ischemia mainly focused on cortical CBF reduction.However,its impact on hemodynamic changes,especially temporal varying characteristics,remains poorly understood.Here,we collected cortical resting-state CBF in rats with left carotid artery blockage during occlusion–reperfusion,and measured the temporal variability and changes in laterality using a novel state-space method.This method was also applied to stroke EEG datasets to validate its effectiveness.After arterial occlusion,the left marginal motor,sensory,auditory,and visual cortices exhibited severe temporal variability impairments.The laterality analysis indicated that affected left regions showed inferior unilateral mean,inter-hemispheric transition probability,time fraction,and laterality duration,while the right side had a higher laterality time fraction and duration.These impairments recovered partially following blood flow restoration.Besides,the ischemic state-space metrics were positively correlated with the pre-occlusion baseline appearance.Stroke patients exhibited impaired temporal variability in the affected ischemic hemisphere.The state-space analysis revealed damaged CBF temporal variability during cerebral ischemia and predicted baseline-ischemia connections. 展开更多
关键词 STATE-SPACE Cerebral blood flow Cerebral ischemia Laser speckle contrast imaging Temporal variability
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Spatiotemporal Variability of Influencing Factors on Tuberculosis Incidence in Jiangsu Province,China during 2011−2021
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作者 Yifan Tang Tenglong Li +7 位作者 Cheng Chen Kai Wang Mingming Chen Junhui Lin Sifan Wang Limei Zhu Chengxiu Ling Qiao Liu 《Biomedical and Environmental Sciences》 2026年第2期234-238,共5页
Tuberculosis(TB),one of the oldest infectious diseases caused by Mycobacterium tuberculosis,poses a considerable challenge to global public health.There are approximately 10 million new TB cases worldwide annually,and... Tuberculosis(TB),one of the oldest infectious diseases caused by Mycobacterium tuberculosis,poses a considerable challenge to global public health.There are approximately 10 million new TB cases worldwide annually,and TB claims the lives of nearly 3 million people each year,making it one of the leading causes of death from a single infectious disease[1].China ranks third globally in terms of TB burden,with approximately 733,000 TB cases reported in 2023[2].Based on the ecological model of health determinants developed by Whitehead and Dahlgren,health determinants can be classified into direct causes. 展开更多
关键词 tuberculosis incidence infectious diseases influencing factors mycobacterium tuberculosisposes spatiotemporal variability China ecological model health determinants jiangsu province
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A Significant Transition of Antarctic Sea Ice Variability in Response to the Shoaling of the Circumpolar Deep Water 被引量:1
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作者 Ruonan CHEN Xiao-Yi YANG Dongxiao WANG 《Advances in Atmospheric Sciences》 2025年第12期2499-2517,共19页
As a crucial component of the Earth’s climate system,Antarctic sea ice has demonstrated significant variability over the satellite era.Here,we identify a remarkable decadal transition in the total Antarctic Sea Ice E... As a crucial component of the Earth’s climate system,Antarctic sea ice has demonstrated significant variability over the satellite era.Here,we identify a remarkable decadal transition in the total Antarctic Sea Ice Extent(SIE).The stage from 1979 to 2006 is characterized by high-frequency(i.e.,seasonal to interannual)temporal variability in SIE and zonal asymmetry in Sea Ice Concentration(SIC),which is primarily under the control of the Amundsen Sea Low(ASL).After 2007,however,sea ice changes exhibit a more spatially homogeneous pattern in SIC and a more temporally long-lasting mode in SIE.Further analysis reveals that sea ice-ocean interaction plays a major role in the low-frequency(i.e.,multiannual)variability of Antarctic sea ice from 2007−22.The related physical process is inferred to manifest as a strong coupling between the surface and the subsurface ocean layers,involving enhanced vertical convection and the downward delivery of the surface anomalies related to ice melting and freezing processes,thus maintaining the SIE anomalies for a longer time.Furthermore,this process mainly occurs in the Amundsen-Bellingshausen Sea(ABS)sector,and the weakened subsurface ocean stratification is the key factor triggering the coupling process in this region.We find that the Circumpolar Deep Water(CDW)over the ABS sector continued to shoal before 2007 and remained stable thereafter.It is speculated that the shoaling of the CDW may be a possible driver leading to the weakening of the subsurface stratification. 展开更多
关键词 Antarctic sea ice low-frequency variability coupling process ocean stratification CDW ice-ocean interaction
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Increase in the variability of terrestrial carbon uptake in response to enhanced future ENSO modulation
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作者 Younong Li Li Dan +2 位作者 Jing Peng Qidong Yang Fuqiang Yang 《Atmospheric and Oceanic Science Letters》 2025年第1期32-38,共7页
El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation an... El Niño-Southern Oscillation(ENSO)is a major driver of climate change in middle and low latitudes and thus strongly influences the terrestrial carbon cycle through land-air interaction.Both the ENSO modulation and carbon flux variability are projected to increase in the future,but their connection still needs further investigation.To investigate the impact of future ENSO modulation on carbon flux variability,this study used 10 CMIP6 earth system models to analyze ENSO modulation and carbon flux variability in middle and low latitudes,and their relationship,under different scenarios simulated by CMIP6 models.The results show a high consistency in the simulations,with both ENSO modulation and carbon flux variability showing an increasing trend in the future.The higher the emissions scenario,especially SSP5-8.5 compared to SSP2-4.5,the greater the increase in variability.Carbon flux variability in the middle and low latitudes under SSP2-4.5 increases by 30.9%compared to historical levels during 1951-2000,while under SSP5-8.5 it increases by 58.2%.Further analysis suggests that ENSO influences mid-and low-latitude carbon flux variability primarily through temperature.This occurrence may potentially be attributed to the increased responsiveness of gross primary productivity towards regional temperature fluctuations,combined with the intensified influence of ENSO on land surface temperatures. 展开更多
关键词 Carbon variability ENSO modulation CMIP6 models
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Interannual variability of boreal summer intraseasonal oscillation over the northwestern Pacific influenced by the Pacific Meridional Mode
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作者 Haoyu Zhou Pang-Chi Hsu +1 位作者 Lin Chen Yitian Qian 《Atmospheric and Oceanic Science Letters》 2025年第1期6-11,共6页
During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the s... During the boreal summer,intraseasonal oscillations exhibit significant interannual variations in intensity over two key regions:the central-western equatorial Pacific(5°S-5°N,150°E-150°W)and the subtropical Northwestern Pacific(10°-20°N,130°E-175°W).The former is well-documented and considered to be influenced by the ENSO,while the latter has received comparatively less attention and is likely influenced by the Pacific Meridional Mode(PMM),as suggested by partial correlation analysis results.To elucidate the physical processes responsible for the enhanced(weakened)intraseasonal convection over the subtropical northwestern Pacific during warm(cold)PMM years,the authors employed a moisture budget analysis.The findings reveal that during warm PMM years,there is an increase in summer-mean moisture over the subtropical northwestern Pacific.This increase interacts with intensified vertical motion perturbations in the region,leading to greater vertical moisture advection in the lower troposphere and consequently resulting in convective instability.Such a process is pivotal in amplifying intraseasonal convection anomalies.The observational findings were further verified by model experiments forced by PMM-like sea surface temperature patterns. 展开更多
关键词 Boreal summer intraseasonal oscillation Interannual variability Pacific Meridional Mode Moisture budget analysis
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Assessment of Genetic Variability and Inter-Relationship for Yield Attributing Traits in Maize (Zea mays L.) Genotypes in White Nile State, Sudan
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作者 Sara Mohammed Abdalla Khalid Abdalla Osman +1 位作者 Abd Elwahab Abdalla Dafaalla Soheap Abdalrahman Yousif 《Agricultural Sciences》 2025年第2期280-289,共10页
Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly... Maize is an important source of calories and protein in human lives in many countries of the world and is the main staple food in Africa, particularly in eastern Africa. In the Sudan, the low yield of maize was mainly due to the use of low yielding landraces. It is necessary to carry out breeding programs that deal with the production of high yielding, adaptable new varieties. Therefore, this study aimed to estimate genetic variability, heritability, genotypic performance and interrelationships among the traits. Ten maize genotypes evaluated at White Nile Research Station Farm, Kosti, of the Agricultural Research Corporation (ARC), Wad Medani Sudan were planted in a randomized complete block design with three replications during the two seasons of 2021 and 2022. Most evaluated genotypes exhibited a wide and significant variation in the 11 measured traits. Genotypic coefficient of variation and genetic advance were recorded for days to 50% tasseling, ear diameter (cm), number of grains per row and grain yield (t/ha) in both seasons. High heritability and genetic advance were recorded for grain yield, ear length, ear height, plant height, number of rows per ear, ear weight, days to 50% tasseling, 100-grain weight and days to 50% silking. Moreover, there was a highly significant and positive correlation of grain yield with number of rows per ear (r = 0.479), ear length (r = 0.381), 100-grain weight (r = 0.344) and days to 50% tasseling (r = 0.214). The highest yielding five genotypes across the seasons were TZCOM1/ZDPSYN (4.2 t/ha), EEPVAH-3 (4.2 t/ha), F2TWLY131228 (4.1 t/ha), PVA SYN6F2 (3.9 t/ha) and EEPVAH-9 (3.8 t/ha) these were needed to check the adaptability, stability and to test major maize growing areas to make sound recommendations for release. 展开更多
关键词 Genetic variability HERITABILITY Correlation MAIZE YIELD
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Interannual variability of surface Indonesian Throughflow and its relationships with Pacific and Indian Oceans derived from satellite observation 被引量:1
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作者 Yingyi Yang Tengfei Xu +4 位作者 Zexun Wei Dingqi Wang Zhongrui Cai Yunzhuo Zhang Yongshun Ma 《Acta Oceanologica Sinica》 2025年第1期1-16,共16页
The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(E... The Indonesian Throughflow(ITF)plays important roles in global ocean circulation and climate systems.Previous studies suggested the ITF interannual variability is driven by both the El Niño-Southern Oscillation(ENSO)and the Indian Ocean Dipole(IOD)events.The detailed processes of ENSO and/or IOD induced anomalies impacting on the ITF,however,are still not clear.In this study,this issue is investigated through causal relation,statistical,and dynamical analyses based on satellite observation.The results show that the driven mechanisms of ENSO on the ITF include two aspects.Firstly,the ENSO related wind field anomalies driven anomalous cyclonic ocean circulation in the western Pacific,and off equatorial upwelling Rossby waves propagating westward to arrive at the western boundary of the Pacific,both tend to induce negative sea surface height anomalies(SSHA)in the western Pacific,favoring ITF reduction since the develop of the El Niño through the following year.Secondly,the ENSO events modulate equatorial Indian Ocean zonal winds through Walker Circulation,which in turn trigger eastward propagating upwelling Kelvin waves and westward propagating downwelling Rossby waves.The Rossby waves are reflected into downwelling Kelvin waves,which then propagate eastward along the equator and the Sumatra-Java coast in the Indian Ocean.As a result,the wave dynamics tend to generate negative(positive)SSHA in the eastern Indian Ocean,and thus enhance(reduce)the ITF transport with time lag of 0-6 months(9-12 months),respectively.Under the IOD condition,the wave dynamics also tend to enhance the ITF in the positive IOD year,and reduce the ITF in the following year. 展开更多
关键词 Indonesian Throughflow(ITF) interannual variability information flow Indian Ocean Dipole(IOD) El Niño-Southern Oscillation(ENSO)
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Gamma-Ray-Induced Genetic Variability for Yield Traits in M4 Generation in Upland Rice
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作者 Habibata Tinta Valentin Stanislas Edgar Traoré +5 位作者 Minimassom Philippe Nikiéma Arlette Wend-Yida Yasmine Kaboré Siébou Palé Hamidou Traoré Mahamadou Sawadogo Djibril Yonli 《Agricultural Sciences》 2025年第2期240-255,共16页
Varietal deficiencies of upland rice lead to a low paddy grain yield. The aim of this study was to mutagenesis upland rice varieties to improve their agronomic performance. Seeds of varieties FKR45N and FKR47N were th... Varietal deficiencies of upland rice lead to a low paddy grain yield. The aim of this study was to mutagenesis upland rice varieties to improve their agronomic performance. Seeds of varieties FKR45N and FKR47N were therefore irradiated with doses 300, 350 and 400 Gy. The irradiated seeds were sown and the panicles of the M1 plants were individually harvested, and then were advanced to M4 using the “one panicle - one progeny” method. The agronomic performance of M4 lines was compared to that of their parent. The gamma ray mutagenesis has induced significant variability in five yield components, i.e., plant height, main panicle length, total numbers of tillers and productive tillers and paddy grain yield between mutant lines. The highest variabilities were shown for the total number of tillers and the number of productive tillers as well as FKR45N (CV% = 40 % and 36%) and FKR47N (CV% = 31% and 30%) mutant lines. Principal component analysis led to rank the mutant lines from each variety in three clusters. The Pearson correlation showed that the paddy grain yield was significantly and positively correlated with the number of productive tillers (r = 0.61) and plant height (r = 0.66) for FKR47N mutant lines, and these correlation coefficients were r = 0.52 and r = 0.51 for FKR45N mutant lines, respectively. Gamma-ray irradiation also induced an earliness of 50% flowering of 62 days after sowing (DAS) in two FKR45N mutant lines and 67 DAS in one of KR47N mutant lines. The paddy grain yield was improved by 120% and 20% in two FKR45N and FKR47N mutant lines, respectively. A dwarf FKR45N mutant line with an early flowering of 67 DAS and a paddy grain yield (2.34 t ha−1) was generated. These results suggested that any positive increase in the six quantitative traits will increase the paddy grain yield. 展开更多
关键词 Upland Rice MUTAGENESIS Genetic variability Agronomic Performance
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Dominant Modes of Spring Drought Variability in Southern China During 1979-2022 and the Associated Drivers
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作者 ZHOU Jia-yu QIU Wen-tian +2 位作者 ZHAO Qing-hong CHEN Xi DENG Kai-qiang 《Journal of Tropical Meteorology》 2025年第4期331-340,共10页
Utilizing the Standardized Precipitation Evapotranspiration Index(SPEI)and ERA5 reanalysis data,this study investigates the variability of spring drought in southern China from 1979 to 2022 and its associated drivers.... Utilizing the Standardized Precipitation Evapotranspiration Index(SPEI)and ERA5 reanalysis data,this study investigates the variability of spring drought in southern China from 1979 to 2022 and its associated drivers.The results indicate that southern China experienced interdecadal changes in SPEI over the past several decades,which can be concluded that drought severity intensified from 1979 to 2010,whereas a transition shift towards increased wetness occurred from 2010 to 2022.The first Empirical Orthogonal Function(EOF1)mode of SPEI variability in southern China accounts for 44.37%of the total variance,reflecting a uniform variation of SPEI across the region.In contrast,the second Empirical Orthogonal Function(EOF2),which explains 24.41%of the total variance,reveals a west-east dipole pattern in SPEI variability.Further analysis indicates that the positive phase of EOF1 is primarily driven by warm sea surface temperature anomalies(SSTAs)in the tropical eastern Pacific.These anomalies induce an anomalous anticyclone over the Philippine Sea,enhancing water vapor transport to southern China during spring.The positive phase of EOF2 is jointly influenced by warm SSTAs in the tropical Indian Ocean and the central Pacific;the latter induces anticyclonic anomalies over the Philippine Sea,which enhance water vapor transport from the western Pacific and increase precipitation in the eastern part of southern China.However,the warm SSTAs in the tropical Indian Ocean trigger an anomalous anticyclone over South Asia,inhibiting water vapor transport from the Bay of Bengal to the western part of southern China and thus reducing precipitation there. 展开更多
关键词 drought variability dominant modes southern China SPRING
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Mood alteration and heart rate variability in patients with cancer on treatment
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作者 Yun-Chen Chang Wei-Nung Liu +1 位作者 Felicia Lin Gen-Min Lin 《World Journal of Cardiology》 2025年第6期1-4,共4页
In this article,Deng and Song showed compelling evidence on the connection between heart rate variability(HRV)alterations and cancer in 127 cancer patients compared with healthy reference individuals,highlighting auto... In this article,Deng and Song showed compelling evidence on the connection between heart rate variability(HRV)alterations and cancer in 127 cancer patients compared with healthy reference individuals,highlighting autonomic nervous system dysfunction as a significant physiological manifestation in cancer patients.We discussed that the reduced HRV may be associated with cancer treatments,e.g.,operation,chemotherapy and pain control and psychological response such as depression and anxiety related to the affected cancer.A management such as medicine to mood disturbances related to cancer has been shown a benefit to improve HRV in cancer patients. 展开更多
关键词 CANCER CHEMOTHERAPY Heart rate variability Mental stress HEART
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Spatial variability and quantitative characterization of thermal shock damage in sandstone under different cooling temperatures
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作者 Shuixin He Baoping Xi +4 位作者 Yangsheng Zhao Jin Xie Yunsheng Dong Luhai Chen Xinxin Yang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4367-4385,共19页
This research employs micro-CT scanning technology to analyze the porosity,pore fractal dimension,and spatial variability of sandstone preheated to 600℃ and subsequently cooled in water at varying temperatures(20℃,6... This research employs micro-CT scanning technology to analyze the porosity,pore fractal dimension,and spatial variability of sandstone preheated to 600℃ and subsequently cooled in water at varying temperatures(20℃,60℃,100℃).The study investigates the mechanisms by which various factors influence thermal shock damage,focusing on the effects of cooling water temperature and the boiling phase transition.The objective is to develop a method for characterizing thermal shock damage that considers spatial variability.The findings indicate that thermal shock damage is limited to a shallow depth beneath the surface,with increased severity near the surface.The boiling phase transition significantly enhances the convective heat transfer coefficient,resulting in substantially higher thermal shock damage when cooled with 100℃ boiling water compared to 20℃ and 60℃ water.Furthermore,for the entire specimen,heating damage exceeds thermal shock damage,and the influence of thermal shock diminishes as specimen size increases.This study addresses the limitations of traditional methods for assessing thermal shock damage that disregard spatial variability and provides practical guidance for engineering projects to manage thermal shock damage more effectively. 展开更多
关键词 SANDSTONE Thermal shock damage MICRO-CT Spatial variability POROSITY Fractal dimension
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Application Value of Electromyography Combined with Heart Rate Variability in the Diagnosis of Diabetic Peripheral Neuropathy
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作者 Wengui Nie Qiang Zhang +2 位作者 Yuehua Li Xiangchen Liu Jie Gao 《Asia Pacific Journal of Clinical Medical Research》 2025年第1期30-38,共9页
Purpose:To explore the clinical value of Electromyography(EMG)and Heart Rate Variability(HRV)in the diagnosis of early DPN and provide the basis for early diagnosis,treatment,and prevention of DPN.Methods:105 patients... Purpose:To explore the clinical value of Electromyography(EMG)and Heart Rate Variability(HRV)in the diagnosis of early DPN and provide the basis for early diagnosis,treatment,and prevention of DPN.Methods:105 patients with type 2 diabetes mellitus(T2DM)in the Changji People’s Hospital were treated from January 2023 to December 2023.They were stratifi ed into DPN-symptomatic(DPN group,n=55)and DPN-asymptomatic(NDPN group,n=50)cohorts based on the presence or absence of clinically confi rmed diabetic peripheral neuropathy.The clinical biochemical indicators,nerve electromyography,and HRV parameters were obtained from electronic medical records,and diff erences in detection results were compared between the two groups.Logistic regression was applied to analyze the infl uencing factors of DPN in diabetes patients.The receiver operating characteristic(ROC)curve was applied to analyze the diagnostic value of EMG combined with other parameters for DPN.Results:From the results of the general information,diabetes duration,glycosylated hemoglobin(HbA1c),low-density lipoprotein cholesterol(LDL-C),total cholesterol(TC)and FBG in the DPN group were significantly differences compared with the NDPN group(p<0.05).There were no statistically significant differences in gender,age years,uric acid,and other general data(p>0.05).Compared with the NDPN group,the motor nerve conduction velocity(MNCV),sensory nerve conduction velocity(SNCV)of the ulnar nerve,median nerve,and tibial nerve in the DPN group were statistically signifi cant(p>0.05).The DPN group had higher average F wave latency and H wave latency in the tested nerve,with statistical signifi cance(p<0.05).HRV parameters decreased signifi cantly(SDNN,rMSSD,PNN50,and SDANN,all p<0.05).ROC analysis showed that the area under the ROC curve(AUC)of the combined diagnosis of DPN by duration of diabetes,HbA1c,EMG,and HRV was 0.897,the accuracy was 82.86%,the sensitivity was 78.00%,and the specifi city was 87.27%.The AUC of the combined diagnosis of the four parameters for DPN was signifi cantly higher than that of each alone(p<0.05).Conclusion:The combination of EMG and HRV has a high value in the assessment of DPN and can be used for early assessment of the extent of the lesion. 展开更多
关键词 Diabetes Peripheral Neuropathy ELECTROMYOGRAPHY Heart Rate variability DIAGNOSIS
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Assessing Water Level Variability in the Mekong Delta under the Impacts of Anthropogenic and Climatic Factors
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作者 Nguyen Cong Thanh Dang Truong An 《Journal of Environmental & Earth Sciences》 2025年第1期123-131,共9页
In recent years,the water level in the Mekong Delta(MD)has undergone changes,attributed to the impacts of anthropogenic activities and climate change.Declining water levels have had implications for various aspects of... In recent years,the water level in the Mekong Delta(MD)has undergone changes,attributed to the impacts of anthropogenic activities and climate change.Declining water levels have had implications for various aspects of life and aquatic ecosystems in the lower basin water bodies.Analyzing long-term trends in rainfall and water levels is crucial for enhancing our understanding.This study aims to examine the evolving patterns of water level and rainfall in the region.Data on water levels and rainfall from observation stations were gathered from the National Center for Hydrometeorological Forecasting,Vietnam,spanning from 2000 to 2014.The assessment of homogeneity and identification of trend changes were conducted using the Standard Normal Homogeneity Test(SNHT)and the Mann-Kendall test.The results indicate that changes in water levels at the Tan Chau and Chau Doc stations have been observed since 2010 due to the operation of flow-regulating structures in the upper Mekong River.Following the commencement of upstream dam operations,the water level at the headwater stations of the Mekong River has been higher than the long-term average during the dry season and lower than the average during the flood season.The study findings highlight the influence of altered rainfall patterns under the impact of climate variability(ICC)on water level trends in the study area.While rainfall plays a significant role in increasing water levels during the flood season,the operation of hydropower dams(UHDs)stands out as the primary factor driving water level reductions in the study area. 展开更多
关键词 Mekong Delta HYDROPOWER Water Level Local Rainfall Climate variability
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Prediction of perioperative complications in colorectal cancer via artificial intelligence analysis of heart rate variability
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作者 Miao-Miao Ge Li-Wen Wang +6 位作者 Jun Wang Jiang Liu Peng Chen Xin-Xin Liu Gang Wang Guan-Wen Gong Zhi-Wei Jiang 《World Journal of Gastrointestinal Surgery》 2025年第4期290-299,共10页
BACKGROUND Heart rate variability(HRV)represents efferent vagus nerve activity,which is suggested to be related to fundamental mechanisms of tumorigenesis and to be a predictor of prognosis in various cancers.Therefor... BACKGROUND Heart rate variability(HRV)represents efferent vagus nerve activity,which is suggested to be related to fundamental mechanisms of tumorigenesis and to be a predictor of prognosis in various cancers.Therefore,this study hypothesized that HRV monitoring could predict perioperative complication(PC)in colorectal cancer(CRC)patients.AIM To investigate the prognostic value of HRV in hospitalized CRC patients.METHODS The observational studies included 87 patients who underwent CRC surgical procedures under enhanced recovery after surgery programs in a first-class hospital.The HRV parameters were compared between the PC group and the non PC(NPC)group from preoperative day 1 to postoperative day(Pod)3.In addition,inflammatory biomarkers and nutritional indicators were also analyzed.RESULTS The complication rate was 14.9%.HRV was markedly abnormal after surgery,especially in the PC group.The frequency-domain parameters(including pNN50)and time-domain parameters[including high-frequency(HF)]of HRV were significantly different between the two groups postoperatively.The pNN50 was significantly greater at Pod1 in the PC group than that in the NPC group and returned to baseline at Pod2,suggesting that patients with complications exhibited autonomic nerve dysfunction in the early postoperative period.In the PC group,HFs were also enhanced from Pod1 and were significantly higher than in the NPC group;inflammatory biomarkers were significantly elevated at Pod2 and Pod3;the levels of nutritional indicators were significantly lower at Pod1 and Pod2;and the white blood cell count was slightly elevated at Pod3.CONCLUSION HRV is independently associated with postoperative complications in patients with CRC.Abnormal HRV could predicted an increased risk of postoperative complications in CRC patients.Continuous HRV could be used to monitor complications in patients with CRC during the perioperative period. 展开更多
关键词 Colorectal cancer Heart rate variability COMPLICATIONS Perioperative period PREDICTION
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Response of Decadal Droughts on the Mongolian Plateau to External Forcings and Internal Variability over the Last Millennium
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作者 Guangyao HAO Weiyi SUN +2 位作者 Jian LIU Liang NING Mi YAN 《Advances in Atmospheric Sciences》 2025年第8期1715-1726,共12页
Since the mid-20th century,the Mongolian Plateau(MP)has experienced decadal droughts coupled with extreme heatwaves,severely affecting regional ecology and social development.However,the mechanisms behind these decada... Since the mid-20th century,the Mongolian Plateau(MP)has experienced decadal droughts coupled with extreme heatwaves,severely affecting regional ecology and social development.However,the mechanisms behind these decadalscale compound heatwavedrought events remain debated.Here,using reconstructions and simulations from the Community Earth System Model Last Millennium Ensemble,we demonstrate that,over the last millennium,decadal droughts on the MP occurred under both warm and cold conditions,differing from recent compound heatwavedrought events.We found that by examining temperature changes during these drought periods,the distinct influences of external forcings and internal variability can be simply and effectively distinguished.Specifically,colddry events were primarily driven by volcanic eruptions that weakened the East Asian summer monsoon and midlatitude westerlies,reducing moisture transport to the MP.In contrast,warmdry events were predominantly induced by internal variability,notably the negative phase of the Atlantic Multidecadal Oscillation and the expansion of the Barents Sea ice extent.The recent extreme compound event was probably influenced by the combined effects of anthropogenic forcings and internal variability.These findings deepen our understanding of how external forcings and internal variability affect decadal drought events on the MP and highlight that recent compound events are unprecedented in the context of the last millennium. 展开更多
关键词 decadal drought Mongolian Plateau temperature anomalies external forcings internal variability
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Central Asian Compound Flooding in 2024 Contributed by Climate Warming and Interannual Variability
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作者 Wenxia ZHANG Lan LI +4 位作者 Tianjun ZHOU Michael BRODY Qing HE Min XU Azamat MADIBEKOV 《Advances in Atmospheric Sciences》 2025年第10期2195-2202,共8页
Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and ca... Extensive flooding swept across large areas of Central Asia,mainly over Kazakhstan and southwestern Russia,from late March to April 2024.It was reported to be the worst flooding in the area in the past 70 years and caused widespread devastation to society and infrastructure.However,the drivers of this record-breaking flood remain unexplored.Here,we show that the record-breaking floods were contributed by both long-term climate warming and interannual variability,with multiple climatic drivers at play across the synoptic to seasonal timescales.First,the heavy snowmelt in March 2024 was associated with above-normal preceding winter snow accumulation.Second,extreme rainfall was at a record-high during March 2024,in line with its increasing trend under climate warming.Third,the snowmelt and extreme rainfall in March were compounded by record-high soil moisture conditions in the preceding winter,which was a result of interannual variability and related to excessive winter rainfall over Central Asia.As climate warming continues,the interplay between the increasing trend of extreme rainfall,interannual variations in soil moisture pre-conditions,as well as shifting timing and magnitudes of spring snowmelt,will further increase and complicate spring flooding risks.This is a growing and widespread challenge for the mid-to high-latitude regions. 展开更多
关键词 compound flooding SNOWMELT extreme rainfall soil moisture climate warming interannual variability
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Crop Calendar Adjustments for Enhanced Rainwater Harvesting in Rice Cultivation of the Plain of Reeds Under Climate Variability
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作者 Thai Duong Phung Kieu Tram Thi Huynh +1 位作者 Van Tuan Phan Dang Truong An 《Research in Ecology》 2025年第2期239-250,共12页
Climate variability significantly impacts agricultural water resources,particularly in regions like Vietnam's Plain of Reeds that heavily utilize rain-fed conditions.This study employs the FAO-AquaCrop model to es... Climate variability significantly impacts agricultural water resources,particularly in regions like Vietnam's Plain of Reeds that heavily utilize rain-fed conditions.This study employs the FAO-AquaCrop model to estimate current and future irrigation water needs for rice cultivation in this critical subregion,aiming to identify optimal sowing schedules(OSS)that enhance rainwater utilization and reduce irrigation dependency.The model was driven by current climate data and future projections(2041-2070 and 2071-2099)derived from downscaled Global Circulation Models under RCP4.5 and RCP8.5 scenarios.The AquaCrop model demonstrated robust performance during validation and calibration,with d-values(0.82-0.93)and R²values(0.85-0.92)indicating strong predictive accuracy for rice yield.Simulation results for efficient irrigation water potential(IWP)under RCP4.5 revealed that strategic shifts in sowing dates can substantially alter water requirements;for instance,advancing the winter-spring sowing to December 5th decreased IWP by 15.6%in the 2041-2070 period,while delaying summer-autumn crop sowing to April 20th increased IWP by 48.6%due to greater reliance on irrigation as rainfall patterns shift.Similar dynamic responses were observed for the 2071-2099 period and for autumn-winter crops.These findings underscore that AquaCrop modeling can effectively predict future irrigation needs and that adjusting cultivation calendars presents a viable,low-cost adaptation strategy.This approach allows farmers in the Plain of Reeds to optimize rainwater use,thereby reducing dependency on supplementary irrigation and mitigating the adverse impacts of climate variability,contributing to more sustainable agricultural water management. 展开更多
关键词 Cultivation Calendar Optimization Irrigation Demand Climate variability Shift Rainwater Harvesting AquaCrop
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